Child safety seat with belted pivot link

ABSTRACT

The invention relates to a child safety seat ( 100 ) adapted to be secured with a safety belt ( 40 ) of a vehicle, comprising a seat shell ( 20 ) for receiving a child; and a seat base ( 10 ) for being placed on a seat of the vehicle. The seat base ( 10 ) comprises a base member ( 1 ) coupled to the seat shell ( 20 ); a pivoting component ( 2 ) connected pivotably to the base member ( 1 ); and an engaging member ( 3 ) configured to engage with the safety belt ( 40 ) of the vehicle, wherein the engaging member ( 3 ) is coupled to the pivoting component ( 2 ) such that a movement of the engaging member ( 3 ) in a certain direction relative to the base member ( 1 ) causes the pivoting component ( 2 ) to pivot away from the base member ( 1 ).

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to European application number17209564.8 filed Dec. 21, 2017, the entire contents of which are herebyincorporated by reference in its entirety.

The invention relates to a child safety seat to be secured with a seatbelt of a vehicle comprising a belted pivot link. The belted pivot link,in particular, allows for reduction of forward rotation of the childsafety seat secured with the vehicle's seat belt in the case of afrontal impact of the vehicle.

Children, until they have reached a certain age or height, may not besecured in vehicles with the seat belts of the vehicle. Because of this,child safety seats must be used for safely transporting children in avehicle. Smaller children, such as babies or toddlers, are held firmlyin their safety seat mounted on a passenger seat of a vehicle with aspecial child restraint system, such as an integral harness system. Forthis age group, a safety seat with a 3-point or 5-point harness using aharness buckle as a coupling device is the safest way to travel. The3-point or 5-point harness of the safety seat firmly secures shouldersand hips of the child in the seat.

Typically, child safety seats are mounted on a seat of the vehicle. Thechild safety seats are either secured by using the vehicle's seatbelt—so-called belted child safety seats—, or by anchoring the childsafety seat on the vehicle seat by using a particular anchoringmechanism, such as an Isofix system.

When using anchoring mechanisms, such as Isofix, the child safety seatis attached by means of rigid links or latches to respective anchorageunits of the vehicle seats, such as loop mountings fixed in the vehicle.These anchoring mechanisms generally employ two anchorage units. Theanchorage units, thus, define a lateral axis of the vehicle.

When using the vehicles's seat belt, specifically a lap belt portion ofthe seat belt, to secure the child safety seat in the vehicle, said lapbelt portion similarly defines a lateral axis of the vehicle. As aconsequence, in either case, the child safety seat tends to rotate aboutsaid lateral axis.

The rotation of the child safety seat about the above-mentioned lateralaxis, either defined by the lap belt portion of the vehicle seat belt orby the anchorage units of the Isofix system, might provide a severedanger and risk of injuries for the child being secured in the childsafety seat in the event of both a frontal collision or a rear-endcollision. In the case of a frontal collision, for instance, the childsafety seat is forced to rotate about the lateral axis, thereby beingpressed downwards in the vehicle seat. With a forward facing childsafety seat, the child sitting in the child safety seat, thus,experiences two rotations: the first is the rotation of the childsecured in the child safety seat caused by the rotation of the childsafety seat itself; the second is the tilting of the child's bodyrelative to the child safety seat. Because of this, the child may berotated forward to such an extent that he/she, specifically his/herhead, hits the back of a front vehicle seat. Similar dangers and risksrelated to extensive forward rotation of the child safety seat may occurif the child safety seat is installed in rearward-facing direction.

In order to avoid unwanted rotation about the lateral axis when thechild safety seat is secured to the vehicle by means of, e.g., thevehicle's seat belt of the vehicle or Isofix anchorage units, the childsafety seat is additionally secured with a so-called anti-rotationdevice. In order to fulfil legislation, such an anti-rotation device isset as a standard requirement. According to UN ECE regulation 129“i-Size”, phase 3, however, an anti-rotation device is no moreobligatory in connection with belted child safety seats. However, therequirements in terms of rotation of the belted child safety seat staythe same also with UN ECE regulation 129.

According to UN ECE regulation 129 it is mandatory to install childsafety seats in rearward-facing direction until the child's age of 15months. Because of this, the suppression of rotation of child safetyseats when installed in rearward-facing direction in the vehicle becomesmore and more important.

Different mechanisms for realizing such an anti-rotation device exist.One such mechanism is the so-called top tether. This mechanism comprisesa tether and a rigid point in the vehicle body. The tether may connectthe rigid point to the top of the child safety seat, thereby preventingforward movement of the child safety seat relative to the vehicle seatin the case of a collision.

A second mechanism for suppressing the rotation of the child safety seatabout the lateral axis is given by a support leg (also called load leg).A support leg for a child safety seat is a means to prevent the rotationof the child safety seat about the lateral axis in case of an impact.Typically, the support leg is attached to the front end of a seat basefor a child safety seat. The support leg supports the seat base againstbeing pressed downward into the vehicle seat in the case of a frontalaccident.

Another mechanism for dealing with the rotation is the so-called “IsofixPivoting Link”, to which European patent no. 1 090 804 is directed. Themechanism using the Isofix pivoting link operates to control themovement of the child safety seat so that forward and rotationalmovement thereof is translated at least in part into (translatory)downward movement of the child safety seat into the vehicle seat. Thus,this mechanism reduces the overall tilting angle of the child in afrontal impact. EP 1 090 804 relies on the Isofix anchorage units.Therefore, the anti-rotation mechanism of EP 1 090 804 is not suitablefor belted child safety seats.

It is, thus, an object of the present invention to provide an anchoragesystem for a belted child safety seat which reduces forward rotation ofthe child safety seat in the case of a frontal accident.

This object is achieved by the child safety seat according to claim 1.Further advantageous embodiments of the present invention are indicatedin claims 2 to 14.

According to the present invention there is provided a child safety seatadapted to be secured with a safety belt of a vehicle, comprising a seatshell for receiving a child; and a seat base for being placed on a seatof the vehicle. The seat base comprises a base member coupled to theseat shell; a pivoting component connected pivotably to the base member;and an engaging member configured to engage with the safety belt of thevehicle. The engaging member is coupled to the pivoting component suchthat a movement of the engaging member in a certain direction relativeto the base member causes the pivoting component to pivot away from thebase member.

Preferably, the engaging member is configured to engage with the lapbelt of the safety belt of the vehicle. The invention is, thus,particularly adapted for belted child safety seats.

Since the engaging member is coupled to the pivoting component such thata movement of the engaging member in a certain direction relative to thebase member causes the pivoting component to pivot away from the basemember, the center of gravity of the entire child safety seat changesits position relative to the axis defined by the portion of the safetybelt of the vehicle engaging with the engaging member and, thus,securing the child safety seat to the vehicle seat. When the childsafety seat is secured in the vehicle with the vehicle's safety belt,the portion of the vehicle's safety belt engaging with the engagingmember defines a first pivoting axis of the child safety seat. The axisabout which the pivoting component is pivotably connected to the basemember defines a second pivoting axis of the child safety seat. In thecase of a frontal impact, according to the invention there occur, thus,two coupled rotations about the first pivoting axis and the secondpivoting axis which lead to a rotation of the child safety seat, on theone hand, but also to a translational movement of the child safety seatdown into the seating portion of the vehicle seat. As a consequence ofthis downward movement, the seat cushion of the seating portion of thevehicle seat gets compressed almost parallel to the seating surface ofthe vehicle seat. A part of the forward rotation is, thus, translatedinto the downward translation. Therefore, less forward rotation of thechild safety seats results. In this sense, the present invention isequipped with a rotation compensation mechanism. In other words, theability of the pivoting component to rotate about a first pivoting axisdefined by the lap belt portion engaging with the engaging member andthe second pivoting axis of the base member introduces an additionaldegree of freedom of the motion of the child safety seat in the event ofa frontal impact. The additional degree of freedom allows for a rotationof the base member, and thus, of the seat shell, relative to thepivoting member which is coupled to the safety belt of the vehicle.

The engaging member which is coupled to the pivoting component isconfigured to engage with the safety belt of the vehicle. The connectionbetween the child safety seat and the vehicle for securing andinstalling the child safety seat in the vehicle is, thus, provided bythe engaging member. Engaging member and pivoting component are,therefore, also termed as belted pivot link.

The base member is coupled to the seat shell. For this, the base memberof the seat base may be separately formed from the seat shell; the basemember may, however, also be integrally formed with the seat shell.Owing to the coupling of the base member to the seat shell, the relativemovement of the base member with respect to the pivoting component isrelated to a respective relative movement of the seat shell with respectto the pivoting component.

Preferably, the child safety seat further comprises a spacing componentcoupled to the engaging member and configured to keep the engagingmember at a predetermined minimal distance from the backrest portion ofthe vehicle seat when the child safety seat is installed in the vehicle.The spacing component aids the user to properly secure the child safetyseat with the safety belt of the vehicle. Specifically, the spacingcomponent prevents the pivoting component to pivot away from the basemember under normal travelling conditions, that is, without the exertionof an extra force on the engaging member. For this, the spacingcomponent preferably is configured to abut against the backrest portionof the vehicle seat when the child safety seat is properly installed inthe vehicle. Thereby, relative movement of the engaging member isprevented under normal traveling conditions. Rotation of the childsafety seat about the first pivoting axis defined by the lap beltportion engaging with the engaging member and the second pivoting axisabout which the pivoting component is pivotably connected to the basemember becomes effectively available only in the case of an impact. Inthe case of an impact, in particular, in the case of a frontal impact,the child safety seat travels a certain distance on the seating portionof the vehicle seat before the safety belt of the vehicles blocks. Thisdistance is sufficient for releasing the spacing component from abutmentagainst the backrest portion. As a consequence, the engaging member isfree to move relative to the base member and to cause the pivotingcomponent to pivot away from the base member. In other words, when aspacing component is used, the anti-rotation device/belted pivot link ofthe invention is activated in the event of an impact.

Advantageously, the relative movement of the engaging member is causedby a force exerted on the base member and pointing away from a backrestportion of the vehicle seat when the child safety seat is placed on thevehicle seat and when the engaging member engages with the safety beltof the vehicle. Preferably, the force is a force of inertia arisingduring a frontal impact of the vehicle. The anti-rotationmechanism/belted pivot link of the invention is configured such as tostart properly working whenever the vehicle is involved in a frontalimpact. In this event, the safety belt of the vehicle blocks. The forceof inertia accelerates the remaining components of the child safetyseat. Thus, the engaging member moves relative to the base member. Inthe case of an impact, the engaging member moves, with regard to thebase member, in the direction of the backrest portion of the vehicleseat. By means of the coupling of the engaging member to the pivotingcomponent the pivoting component pivots away from the base member. Thisallows for the two coupled rotations as described before to start. Thisleads to the suppression of the forward rotation of the child safetyseat, as described above.

Advantageously, the pivoting component is rigidly formed. That is, thepivoting component has a certain rigidity and stiffness for ensuringthat the child safety seat is securely coupled to the safety belt of thevehicle.

Preferably, the axis about which the pivoting component is pivotablyconnected to the base member is positioned at the portion of the seatbase facing the backrest portion of the vehicle seat when the childsafety seat is installed in the vehicle. This position makes it possiblefor the seat shell of the child safety seat to rotate such as toeffectively compensate, at least in part, for the downward rotation inthe case of a frontal impact. That is, by positioning the pivoting axisat the portion of the seat base facing the backrest portion of thevehicle seat, that is, at the rear side of the seat base, when the childsafety seat is properly installed in the vehicle, in the case of anaccident, the portions of the seat shell at the front side of the seatbase rotate less toward the seating surface of the vehicle seat than therear portions of the seat shell. By this, downward rotation is moreeffectively translated into downward translation.

Preferably, the pivoting component and the engaging member areintegrally formed. This makes the manufacturing process easier.

Advantageously, the engaging member is positioned at a certain distancefrom the axis about which the pivoting component is pivotably connectedto the base member. The distance between the engaging member and thepivoting axis at which the pivoting member is connected to the basemember influences the overall movement of the child safety seat in theevent of an accident. By choosing said distance properly it is possibleto suppress the forward rotation to a higher extent. In addition to thedistance of the engaging member, and, thus, the safety belt, from thepivoting axis, also the vertical distance of the center of gravity ofthe child safety seat from the pivoting axis influences the overallmotion of the child safety seat. Therefore, by choosing the relation ofsaid two distances properly, the translation of the downward rotation todownward translation is enhanced. Advantageously, the two distances arein the same range.

Advantageously, the engaging member comprises a belt guide, preferably abelt guide with a hook-shaped portion configured to receive a portion ofthe seat belt of the vehicle. The hook shape is particularly useful forsecurely guiding and receiving the safety belt of the vehicle.Advantageously, the belt guide may also comprise a belt clamp.

Advantageously, the force causes the engaging member to move closer to aplane comprising the center of gravity of the child safety seat andparallel to the lower surface of the seat base so as to reduce thevertical distance of the engaging member from the horizontal plane goingthrough the center of gravity of the child safety seat. Therefore, e.g.,in the case of a frontal impact, during said impact the lever armrelated to the rotation of the child safety seat about the firstpivoting axis defined by the lap belt portion engaging with the engagingmember gets shorter and shorter. Because of this, downward movement ofthe child safety seat and, specifically, of the seat shell is initiated.By this, the child safety seat, specifically the seat base, is presseddown into the seating portion of the vehicle seat. This downwardmovement is almost parallel to the seating portion of the vehicle seat.Therefore, downward rotation is reduced, since the overall movement has,at least, partially been transformed into downward translatory movement.

According to some aspects of the invention, it is advantageous that theengaging member is located between the base member and the pivotingcomponent. In this case, it might also be advantageous if the engagingmember is movably coupled to the pivoting component so that movement ofthe engaging member towards the axis about which the pivoting componentis pivotably connected to the base member causes the seat shell to pivotaway from the pivoting component. It is further advantageous if thepivoting component extends over at least a part of the lower surface ofthe seat base. Preferably, the engaging member is wedge shaped or theengaging member comprises a hinging mechanism. Since the safety belt ofthe vehicle is located between the base member and the pivotingcomponent, the vehicle is particularly securely coupled with the seatbase. Furthermore, if the movement of the engaging member along thepivoting component is coupled to the pivoting of the seat shell awayfrom the pivoting component, then there is a mechanism which compensatesfor the downward rotation of the child safety seat in the case of anaccident. The engaging member, in this case, is configured such as tolimit downward rotation of the center of gravity of the child safetyseat by rotating the seat shell away from and upward with respect to thepivoting component. The pivoting component which preferably is at leasta part of the lower surface of the seat base, is then, pressed down intothe seating portion of the vehicle seat. Downward rotation of the childsafety seat is, in this case, thus reduced by the upward rotation of theseat shell caused by the engaging member. The downward rotation causedby the vehicle accident and the upward rotation caused by the engagingmember as described above partially compensate one another.

Specific embodiments of the invention will now be described by way ofexample and with reference to the accompanying drawings, in which:

FIG. 1 shows a shows a side view of the first embodiment of the childsafety seat of the invention under normal travelling conditionsinstalled on a vehicle seat;

FIG. 2 is an enlarged perspective view of the belted pivot link of thechild safety seat in accordance with the first embodiment;

FIGS. 3a and 3b are a sequence of the movement of the child safety seatin accordance with the first embodiment during a frontal impact of thevehicle;

FIG. 4a shows a side view of the child safety seat in accordance withthe second embodiment of the invention installed in the vehicle undernormal conditions;

FIGS. 4b and 4c are a sequence of the movement of the child safety seatin accordance with the second embodiment during a frontal impact of thevehicle;

FIG. 5a shows a side view of the child safety seat in accordance withthe third embodiment of the invention installed in the vehicle undernormal conditions;

FIGS. 5b and 5c are a sequence of the movement of the child safety seatin accordance with the third embodiment during a frontal impact of thevehicle.

FIG. 1 shows a first embodiment of the child safety seat 100 of thepresent invention. The child safety seat 100 is shown to be secured by alap belt 40 of the seat belt of a vehicle, and placed on the seatingportion 31 of a vehicle seat 30. In FIG. 1 the child safety seat 100 isshown under normal travelling conditions. The child safety seat 100comprises a seat shell 20 and a seat base 10. The seat base 10 comprisesa base member 1, a pivoting component 2 and an engaging member 3. In theshown case, the seat shell 20 is an infant carrier which is releasablyconnected to the base member 1. It is, however, also possible that seatshell and seat base are integrally formed, or that the seat shell istightly or non-removably attached to the seat base. The seat shell 20 isplaced in rearward-facing direction, i.e., the child is positioned inthe child safety seat in direction opposite to the normal drivingdirection. Further, it is shown that the seat base 1 also comprises arebound bar 6. The rebound bar 6 extends vertically from the base member1 of the seat base 10. The rebound bar 6 is configured to prevent theseat base 10 from bouncing back, that is, from upward rotation from theseating portion 31 of the vehicle seat 30, in the case of a frontalimpact. The rebound bar 6 is further configured to prevent the seat base10 from rotation in the case of a rear impact of the vehicle.

The pivoting component 2 is pivotably connected to the base member 1.The pivoting component 2 is connected to the base member 1 at a pivotingaxis 4. The pivoting axis 4 is positioned at the rear side of the seatbase 10, that is, at the portion of the seat base 10 which is facing thebackrest portion 32 of the vehicle seat 30, when the child safety seat100 is properly installed in the vehicle. Coupled to the pivotingcomponent 2 there is an engaging member 3. In the embodiment shown inFIG. 1, the pivoting component 2 and the engaging member 3 areintegrally formed. The engaging member 3 engages with the lap belt 40 ofthe safety belt of the vehicle. For this, the engaging member 3 is hookshaped. During the installation of the child safety seat 100 the lapbelt 40 is fed through the hook. The hook functions, thus, as a beltguide. This allows for securing the child safety seat 100 by means ofthe safety belt of the vehicle. The pivoting component 2 and theengaging member 3 are, therefore, also denoted as belted pivot link.

Furthermore, there is a spacing component 5 attached to the engagingmember 3. The spacing component 5 ensures that the engaging component 3is kept at a predetermined position during installation of the childsafety seat 100 and under normal conditions. Specifically, the spacingcomponent 5 prevents the belted pivot link from rotation under normalconditions. As shown, the spacing component 5 abuts against the backrestportion 32 of the vehicle seat 30. This is to say that the belted pivotlink is disabled under normal conditions. As will be described in moredetail with respect to FIGS. 3a and 3b below, a frontal impact may serveas a trigger which activates the belted pivot link, i.e., which movesthe child safety seat 100 sufficiently far away from the backrestportion 32 of the vehicle seat such that the engaging member 3 and,thus, the pivoting component 2 are allowed to rotate/pivot about thepivoting axis 4, and thus, to move relative to the base member 1. In theconfiguration shown in FIG. 1, that is, under normal conditions, thespacing component 5 is dimensioned such that the pivoting component 2 issubstantially vertical with regard to the seating surface of the vehicleseat 30. The shaded circle sector 51 defines the minimal distance of theengaging member 3 from the intersection of the seating portion 31 andthe backrest portion 32 of the vehicle seat 30. Said minimal distance 51is preferably 10 cm or larger.

FIG. 2 shows the belted pivot link of the first embodiment of theinvention in greater detail. From FIG. 2 it becomes manifest that twobelted pivot links are used. Each of the belted pivot links comprises apivoting component 2, an engaging member 3, and a spacing component 5.The two belted pivot links are pivotably connected to the base member 1of the seat base. In this case, a pivoting axle 7 is used. The pivotingaxle 7 also defines the respective pivoting axis. The seat base is shownto be placed on the seating portion 31 of the vehicle seat. Furthermore,the spacing components 5 ensure that the engaging member 3 maintains apredetermined minimal distance from the backrest portion 32 of thevehicle seat, as described already above in relation to FIG. 1.

FIGS. 3a and 3b show the trajectory of the child safety seat 100 of thefirst embodiment during a frontal impact of the vehicle. During afrontal impact, the child safety seat 100 experiences a force of inertiaF owing to the sudden deceleration of the vehicle. This force of inertiaF drives the child safety 100 in the forward direction, as indicated bythe arrow F in FIGS. 3a and 3b . That is, the child safety seat 100 isaccelerated away from the backrest portion 32 of the vehicle seat.

The child safety seat 100 shown in FIGS. 3a and 3b comprises a spacingcomponent 5 which is connected to the engaging member 3. As describedpreviously with respect to FIG. 1, the spacing component 5 is configuredto prevent rotation/pivoting of the engaging member 3 and the pivotingcomponent 2 under normal travelling conditions. In the event of afrontal impact, the child safety seat 100 travels a certain distance onthe seating portion 31 of the vehicle seat and away from the backrestportion 32. This is, because the lap belt 40 of the safety belt of thevehicle blocks only after a certain force/load is exerted on it. Thedistance is sufficiently large as to allow for rotation/pivoting of theengaging member 3 with the pivoting component 2 about the pivoting axis4. That is, the distance is large enough so as to avoid abutment of thespacing component 5 against the backrest portion 32 of the vehicle seat.This can be expressed also as follows: the anti-rotation mechanism ofthe invention, i.e., the belted pivot link, is disabled when the childsafety seat is installed in the vehicle and in use under normalconditions; in the case of an frontal impact, the anti-rotationmechanism/belted pivot link gets activated.

FIG. 3a shows the child safety seat 100 in an early stage of the frontalimpact. There is basically no contact with the seating portion 31 of thevehicle seat. The child safety seat 100 is secured by means of a lapbelt 40. It is assumed here that the lap belt 40 is already blocked bythe force exerted on it. That is, the lap belt 40 is already exerting,in turn, a respective restraining force on the belted pivot link of theseat base 10. Specifically, the restraining force is exerted by the lapbelt 40 on the engaging member 3. Since in the first embodiment thepivoting component 2 and the engaging member 3 are integrally formed,the same restraining force is exerted on the pivoting component 2.Because of this, the engaging member 3, and, thus, the pivotingcomponent 2 is rotated away from the base member 1 of the seat base 10upon movement of the base member 1. The engaging member 3 moves/rotatesrelative to the base member 1 in a direction towards the backrestportion 32. The rotation of the engaging member 3 and of the pivotingcomponent 2 is about the pivoting axis 4. The rotation angle 8 of thepivoting component 2 relative to the base member 1 is also shown in FIG.3 a.

In addition to the rotation/pivoting of the pivoting component 2 awayfrom and relative to the base member 1 about the pivoting axis 4, thepivoting component 2 rotates about an axis defined by the lap beltportion which is guided through the engaging member 3. Therefore, thechild safety seat 100 performs two coupled rotations in the case of afrontal impact. This, in particular, allows for an upward rotation ofthe child safety seat 100. This is sketched in FIG. 3a . This means thatthe front part of the seat base and, thus, of the child safety seat 100,that is, the leading part with regard to the travelling direction, is ata raised position compared to the rear part of the seat base. This ispossible because the base member 1 is allowed to rotate about thepivoting axis 4. Therefore, the force F acting on the center of gravityof the child safety seat causes the child safety seat to rotate upwardwith regard to the pivoting axis defined by the lap belt portion guidedthrough the engaging member 3.

Furthermore, during the frontal impact, the pivoting component 2 isrotated farther and farther away from the base member 1. This rotationmoves the engaging member 3 closer to a horizontal plane going throughthe center of gravity of the child safety seat 100. This implies thatthe lever arm related to the rotation of the child safety seat 100 aboutthe pivoting axis defined by the lap belt 40 engaging with the engagingmember 3 gets shorter and shorter. Therefore, the momentum which triesto rotate the child safety seat 100 is not constant, but it ratherchanges. The seat base 10 and the child safety seat 100 do notexperience a mere rotation, but they are subjected to both a rotationaland translational movement. In other words, a portion of the downwardrotation is transferred into translational movement down into seatingportion 31 of the vehicle seat.

FIG. 3b shows the child safety seat 100 at a later stage of the frontalimpact, that is, at a stage later than that shown in FIG. 3a . Theshortening of the lever arm during the rotation of the pivoting member 2away from the base member 1, as described above in relation to FIG. 3a ,initiates a downward movement of the child safety seat 100 toward theseating portion 31 of the vehicle seat. Once the lower surface of theseat base 10 touches the seating portion 31 of the vehicle seat, therespective seat cushion gets compressed. The downward movement createsan extensive compression of the seat cushion almost parallel to thesurface of the seating portion 31. Consequently, the translationalmovement of the seat base 10 down into the seat cushion of the seatingportion 31 reduces the forward rotational contribution to the overallmovement of the child safety seat 100 during a frontal impact.

The extent to which the lower surface of the seat base 10 becomesparallel with regard to the seating surface of the vehicle seat depends,in particular, on the relation between the distance from the engagingmember 3 to the pivoting axis 4 of the base member and the distance fromthe pivoting axis 4 of the base member to the center of gravity of thechild safety seat 100.

FIG. 4a shows a child safety seat 200 according to a second embodimentof the present invention. The child safety seat 200 is shown to besecured by a lap belt 40 of the seat belt of a vehicle, and placed onthe seating portion 31 of a vehicle seat. In FIG. 4a the child safetyseat 200 is shown under normal travelling conditions. The child safetyseat 200 comprises a seat shell 220 and a seat base 210. The same asdescribed with respect to the first embodiment, the seat shell 220 isplaced in rearward-facing direction. The same as the seat base of thechild safety seat of the first embodiment of the invention, describedabove in relation to FIGS. 1-3, the seat base 210 comprises a basemember 201, a pivoting component 202 and an engaging member 203. Thearrangement of the base member 201, the pivoting component 202, and theengaging member 203 differs, however, with respect to the firstembodiment.

The pivoting component 202 is pivotably connected to the base member201. In this embodiment, the pivoting component 202 provides the lowersurface of the seat base 210. That is, the pivoting component 202 is orcomprises the lower cover of the seat base 210. The pivoting component202 comprises at least a portion which touches the upper surface of theseating portion 31 of the vehicle seat, when the child safety seat 200is installed in the vehicle. The pivoting component 202 is connected tothe base member 201 at a pivoting axis 204. The pivoting axis 204 ispositioned at the rear side of the seat base 210, that is, at theportion of the seat base 210 which is facing the backrest portion 32 ofthe vehicle seat, when the child safety seat 200 is properly installedin the vehicle. The engaging member 203 is coupled to the pivotingcomponent 202. According to the second embodiment shown in FIG. 4a , theengaging member 203 is moveable along the surface of the pivotingcomponent 202 pointing towards the base member 201.

The engaging member 203 engages with the lap belt 40 of the safety beltof the vehicle. With regard to the second embodiment shown in FIG. 4a ,the lap belt 40 is guided through the seat base 210 in a space locatedbetween the base member 201 and the pivoting component 202. Furthermore,said space is confined by the engaging member 203. The same as for thefirst embodiment, the pivoting component 202 and the engaging member 203can, therefore, also be denoted as a belted pivot link.

The engaging member 203 is wedge shaped. For instance, the engagingmember 203 may be given by a ramp which is moveable along the pivotingcomponent 202 and between the pivoting component 202 and the base member203. The engaging member 203 is adapted to interact with a respectivecut-out 209 of the base member 201. The cut-out 209 has an inclinedsurface matching the inclination of the wedge or ramp of the engagingmember 203. Because of this, the engaging member 203 causes the basemember 201 to rotate away from the pivoting component 202 when theengaging member 203 is driven closer to the pivoting axis 204. Themaximal rotation or inclination angle of the base member 201 relative tothe pivoting component 202 may be controlled by the dimensions of theengaging member 203 and the respective cut-out 209. In addition to theinclination angle of the wedge or ramp of the engaging member 203, inparticular, the longitudinal extension of the engaging member 203, i.e.,its extension in the normal travelling direction of the vehicle, whenthe child safety seat 200 is properly installed in the vehicle,determines the rotation of the base member 201 in the case of a frontalimpact. Furthermore, the longitudinal extension of the engaging member203 determines the minimal distance of the lap belt 40 engaging with theengaging member 203 from the backrest portion 32 of the vehicle seat. Inthis sense, the engaging member 203 comprises a spacing component.

FIGS. 4b and 4c show the trajectory of the child safety seat 200 of thesecond embodiment during a frontal impact of the vehicle. Analogously toFIGS. 3a and 3b the force of inertia owing to the sudden deceleration ofthe vehicle acting on the child safety seat is denoted by F.

FIG. 4b shows the child safety seat 200 in an early stage of the frontalimpact. The child safety seat 200 is secured by means of a lap belt 40.It is assumed here that the lap belt 40 is already blocked by the forceexerted on it. That is, the lap belt 40 is already exerting, in turn, arespective restraining force on the belted pivot link of the seat base210. Specifically, the restraining force is exerted by the lap belt 40on the engaging member 203. Since in the second embodiment the engagingmember 203 is moveable along the pivoting component 202 the restrainingforce retains the engaging member 203 while the other components of thechild safety seat 200, such as the seat shell 220, base member 201, andpivoting component 202 are driven into forward direction by the force ofinertia F. During this relative movement of the engaging member 203 withregard to the other components of the child safety seat 200,specifically with regard to the pivoting component 202 and the basemember 201, the base member 201 rotates away from the pivoting component202. The rotation occurs about the pivoting axis 204. The wedge or rampof the engaging member 203 interacts with the cut-out 209 of the basemember 201 such as to move apart the base member 201 and the pivotingcomponent 202. Because of this, the relative rotation of the base member201 away from the pivoting component 202 creates an upward rotation ofthe seat shell 220 of the child safety seat 200 which is opposite to thedownward rotation about the axis defined by the lap belt portionengaging with the engaging member 203. The upward rotation, thus,compensates, at least in part, for the downward rotation.

The same as described in detail with regard to the first embodiment ofthe invention, the upward and downward rotations are coupled to oneanother. This is equivalent to say that at least a portion of thedownward rotation is transferred into a downward translation. Because ofthis, the child safety seat 200 is equipped with an anti-rotationmechanism.

FIG. 4c shows the child safety seat 200 at a later stage of the frontalimpact, that is, at a stage later than that shown in FIG. 4b . In theshown configuration, the rotation angle 208 of the base member 201relative to the pivoting component 202 has reached its maximal value. Inthis case, the wedge or ramp of the engaging member 203 abuts againstthe base member 201 such that further movement of the engaging member203 towards the pivoting axis 204 is not possible any more. The pivotingcomponent 202 is pressed down into the seating portion 31 of the vehicleseat. As described above with respect to the first embodiment, thedownward movement creates an extensive compression of the seat cushionalmost parallel to the surface of the seating portion 31. In terms ofthe second embodiments, this means that the more parallel the pivotingcomponent 202 is depressed into the seating portion 31 of the vehicleseat, the more efficiently the forward rotation is suppressed.

FIG. 5a shows a third embodiment of the child safety seat 300 inaccordance with the invention. The child safety seat 300 of the thirdembodiment is similar to the child safety seat of the second embodiment.In particular, for securing the child safety seat 300 in the vehicle,the lap belt 40 is guided through a space between the base member 301and the pivoting component 302 of the seat base 310. The seat shell 320is placed in rearward-facing direction.

According to the third embodiment, the pivoting component 302 ispivotably connected to the base member 301 by means of a two hinges 303and 313. The hinges 303 and 313 are preferably kinematic hinges. Thehinge 303 is connected to the pivoting component 302 at the pivotingaxis 3041, and it is connected to the base member 301 at the pivotingaxis 3043. The hinge 313 is connected to the pivoting component 302 atthe pivoting axis 3042, and it is connected to the base member 301 atthe pivoting axis 3044. The hinge 303 is the engaging member 303 of theseat base 310 of the child safety seat 300. As can be seen from FIG. 5a, the lap belt 40 abuts on the hinge 300. The hinge/engaging member 303and the hinge 313 are configured such that a relative movement of thepivoting component 302 and the base member 301 causes the base member301 to pivot away from the pivoting component 302 in such a way that thefront part of the base member 301, i.e., the part which is farther awayfrom the backrest portion 32 of the vehicle seat, moves faster than therear part of the base member 301, i.e., the part which is closer to thebackrest portion 32. This movement has the effect of an upward rotationof the base member 301 relative to the pivoting component 302. Such amovement can be achieved, e.g., by choosing the pivoting axes 3041,3042, 3043, and 3044, as well as the length of the hinge/engaging member303 and hinge 313 accordingly.

The functioning of the anti-rotation mechanism of the third embodimentis, thus, similar to that of the second embodiment. In order to providethe upward rotation of the base member 301 and the seat shell 320 in thecase of an impact, a hinging mechanism is used, however, instead of awedge or ramp.

FIGS. 5b and 5c show the trajectory of the child safety seat 300 of thethird embodiment during a frontal impact of the vehicle. Analogously toFIGS. 4b and 4c the force of inertia owing to the sudden deceleration ofthe vehicle acting on the child safety seat is denoted by F.

FIG. 5b shows the child safety seat 300 in an early stage of the frontalimpact. The child safety seat 300 is secured by means of a lap belt 40.It is assumed here that the lap belt 40 is already blocked by the forceexerted on it. That is, the lap belt 40 is already exerting, in turn, arespective restraining force on the belted pivot link of the seat base310. Specifically, the restraining force is exerted by the lap belt 40on the engaging member 303. Since in the third embodiment the engagingmember 303 is a hinge pivotably connecting the pivoting component 302and the base member 301 the restraining force tilts engaging member 303in a more upright position while the other components of the childsafety seat 300, such as the seat shell 320, base member 301, andpivoting component 302 are driven into forward direction by the force ofinertia F. During this relative movement of the engaging member 303 withregard to the other components of the child safety seat 300,specifically with regard to the pivoting component 302 and the basemember 301, the base member 301 pivots away from the pivoting component302. Said movement of the base member 301 and the pivoting component 302leads to tilt or to rotate the hinge/engaging member 303 into an uprightposition. This implies that the distance between the base member 301 andthe pivoting component 302 gets larger. As described before, thehinge/engaging member 303 and the hinge 313 are configured such that thefront part of the base member 301 moves faster away from the pivotingcomponent 302 than the rear part of the base member 301. This leads to acombined rotational and translational movement of the base member 301relative to the pivoting component 302.

This movement compensates, at least in part, the downward rotation ofthe child safety seat 300 about the axis defined by the lap belt portionengaging with the engaging member 303. Said compensation occursanalogously to that described above in relation to the secondembodiment.

FIG. 5c shows the child safety seat 300 at a later stage of the frontalimpact, that is, at a stage later than that shown in FIG. 5b . In theshown configuration, the rotation angle 308 of the base member 301relative to the pivoting component 302 has substantially reached itsmaximal value. In this case, the base member 303 is close to abuttingthe pivoting member 302, and the hinge/engaging member 303 is in asubstantially upright position. The pivoting component 302 is presseddown into the seating portion 31 of the vehicle seat. As described abovewith respect to the second embodiment, that the more parallel thepivoting component 302 is depressed into the seating portion 31 of thevehicle seat, the more efficient the suppression of the forward rotationgets.

Although in the embodiments presented before the child safety seat wasshown to be installed in rearward-facing direction, i.e., the child ispositioned in the child safety seat in direction opposite to the normaldriving direction, the invention can equally be used for child safetyseats installed in forward-facing direction, i.e., when the child ispositioned in the child safety seat in direction of the normal drivingdirection.

List of Reference Numerals

-   100 child safety seat of the first embodiment-   10 seat base of the child safety seat 100-   1 base member of the seat base 10-   2 pivoting component of the seat base 10-   3 engaging member of the seat base 10-   4 pivoting axis of the child safety seat 100-   5 spacing component of the child safety seat 100-   51 circle sector indicating the minimal distance of the engaging    member 3 from the intersection of the seating portion 31 and the    backrest portion 32-   6 rebound bar of the child safety seat 100-   7 pivoting axle of the child safety seat 100-   8 rotation angle of the pivoting component 2 relative to the base    member 1-   20 seat shell of the child safety seat 100-   200 child safety seat of the second embodiment-   210 seat base of the child safety seat 200-   201 base member of the seat base 210-   202 pivoting component of the seat base 210-   203 engaging member of the seat base 210-   204 pivoting axis of the child safety seat 200-   208 rotation angle of the pivoting component 202 relative to the    base member 201-   209 cut-out of the base member 201-   220 seat shell of the child safety seat 200-   300 child safety seat of the third embodiment-   310 seat base of the child safety seat 300-   301 base member of the seat base 310-   302 pivoting component of the seat base 310-   303 hinge/engaging member of the seat base 310-   313 hinge of the seat base 310-   3041 pivoting axis of the engaging member 303 at the pivoting    component 302-   3042 pivoting axis of the hinge 313 at the pivoting component 302-   3043 pivoting axis of the engaging member 303 at the base member 301-   3044 pivoting axis of the hinge 313 at the base member 301-   308 rotation angle of the pivoting component 202 relative to the    base member 201-   320 seat shell of the child safety seat 200-   30 vehicle seat-   31 seating portion of the vehicle seat 30-   32 backrest portion of the vehicle seat 30-   40 lap belt-   F force of inertia

The invention claimed is:
 1. A child safety seat adapted to be securedwith a safety belt of a vehicle, comprising: a seat shell for receivinga child; and a seat base for being placed on a seat of the vehicle;wherein the seat base comprises: a base member coupled to the seatshell; a pivoting component connected pivotably to the base member; andan engaging member configured to engage with the safety belt of thevehicle; wherein the engaging member is coupled to the pivotingcomponent such that a movement of the engaging member in a certaindirection relative to the base member causes the pivoting component topivot away from the base member; wherein the relative movement of theengaging member is caused by a force exerted on the base member andpointing away from a backrest portion of the vehicle seat when the childsafety seat is placed on the vehicle seat and when the engaging memberengages with the safety belt of the vehicle.
 2. The child safety seataccording to claim 1, further comprising a spacing component coupled tothe engaging member and configured to keep the engaging member at apredetermined minimal distance from the backrest portion of the vehicleseat when the child safety seat is installed in the vehicle.
 3. Thechild safety seat according to claim 2, wherein the spacing component isconfigured to abut against the backrest portion of the vehicle seat whenthe child safety seat is installed in the vehicle, thereby preventingrelative movement of the engaging member under normal travelingconditions.
 4. The child safety seat according to claim 1, wherein theengaging member comprises a belt guide with a hook-shaped portionconfigured to receive a portion of the seat belt of the vehicle.
 5. Thechild safety seat according to claim 1, wherein the pivoting componentis rigidly formed.
 6. The child safety seat according to claim 1,wherein an axis about which the pivoting component is pivotablyconnected to the base member is positioned at the portion of the seatbase facing the backrest portion of the vehicle seat when the childsafety seat is installed in the vehicle.
 7. The child safety seataccording to claim 1, wherein the pivoting component and the engagingmember are integrally formed.
 8. The child safety seat according toclaim 7, wherein the engaging member is positioned at a certain distancefrom the axis about which the pivoting component is pivotably connectedto the base member.
 9. The child safety seat according to claim 7,wherein the force further causes the engaging member to move closer to aplane comprising the center of gravity of the child safety seat andparallel to the lower surface of the seat base so as to reduce thevertical distance of the engaging member from the horizontal plane goingthrough the center of gravity of the child safety seat.
 10. The childsafety seat according to claim 1, wherein the engaging member is locatedbetween the base member and the pivoting component.
 11. The child safetyseat according to claim 10, wherein the engaging member comprises ahinging mechanism.
 12. The child safety seat according to claim 10,wherein the engaging member is movably coupled to the pivoting componentso that movement of the engaging member towards the axis about which thepivoting component is pivotably connected to the base member causes thepivoting component to pivot away from the base member.
 13. The childsafety seat according to claim 10, wherein the pivoting componentextends over at least a part of the lower surface of the seat base. 14.The child safety seat according to claim 10, wherein the engaging memberis wedge shaped.